Robert Altman would be proud. His signature ensemble filmmaking style has become the norm rather than the exception in dramatic series. However magnetic the leads, they’re invariably surrounded by distinctive character players who get multiple chances to shine across a typical season.

Which creates an annual knotty problem for Emmy voters as they consider the supporting categories. Some turns can be singled out as guest actor or actress — late-1980s additions conveniently allowing the academy to spread a little more wealth around. But nominators are still faced with tapping only a select few per skein. Even more mysteriously, they’re wont to proffer a nod one year, only to deny one the next for the very same role. For example, the first year “Modern Family” was eligible, everyone in the cast but Ed O’Neill received a nom. For the next three years, the entire ensemble was recognized. But this year, both O’Neill and two-time winner Eric Stonestreet came up short, despite solid seasons.

Creatives submit a striking episode for each contender and hope voters will be so guided, but there are no guarantees. Asked why “Game of Thrones” is represented by Lena Headey this year instead of 2013’s Emilia Clarke, nominated director Neil Marshall muses, “I don’t know. … Sometimes they get a really, really strong story arc throughout the series, and sometimes they’re slightly less. I don’t know.”

Can voters possibly commit the time to view all the hand-picked work, and base their selections on those episodes alone? It’s doubtful. One Emmy voter, who confesses to being “overwhelmed” by annual screeners, merely says, “You think about who stands out. You sort of get a feeling.”

Several standout members of strong ensembles generate enough of a feeling to secure an annual slot. Aaron Paul sends Jesse Pinkman deeper into hell in each season of “Breaking Bad,” even though his co-star Dean Norris had a dramatic death. Maggie Smith gets all the good “Downton Abbey” lines, while making even the weaker ones zing, and her co-star Joanne Froggett had a dramatic rape storyline this year. Christine Baranski has just earned her fifth consecutive nom as the senior partner, torn between doing good and doing well, on “The Good Wife.” Archie Panjabi is equally reliable on the same show, but after winning in 2010 she’s been nominated twice since and snubbed twice more.

Thinking more deeply about Headey — without taking anything away from Clarke — Marshall suggests nominators may indeed be moved more by a striking overall impression than by a single episode’s highlights. “Sometimes characters do come to the forefront a little bit more, and other times they’re less known.”

This season Headey’s character saw a son killed and a brother placed on trial, “a very involved story,” Marshall says. “So it seems like she’d stand out in the crowd a little bit. We’re talking like increments here, considering it’s such a strong ensemble.”

On that logic, it was no surprise to see nominee Josh Charles reappear on the roster after two lean years. Even before Will Gardner’s headline-making surprise assassination, endlessly aired promos saw him roaring and sweeping his desk clean at the news of defecting partner (and occasional lover) Julianna Margulies. Her departure brought out the madman in Will, who schemed ruthlessly to steal clients and make mischief in episode after episode. That’s acting with a capital A. And the death of his character — making this the last chance for Charles to be rewarded for the show — probably didn’t hurt.

Previous nominee Alan Cumming and co-stars Zach Grenier and Matt Czuchry had stellar “Good Wife” seasons, too. But the incremental elements came together for Charles to bring home the bacon.